Secrets Hidden in Images (Steganography) - Computerphile

If you download this video you'll discover that every single frame contains "I'm the editor working hours in the basement, please send help"

Steganosaurus is my favourite dinosaur.

From now on, I'm going to watermark all my image work with the tragedy of darth plaguis the wise

Every time Dr. Pound makes a video he goes "oh I've written a program for this..." then they never show us the code! It would be fantastic if you guys could share Dr. Pound's work for learning purposes.

Truly this is a remarkable area of study. Why just the other day I was looking at what appeared at first to be a picture of a herd of braying donkeys. It was only with careful scrutiny of the image I realized that O was actually staring at a picture of parliament.

A very interesting video on how e.g. the entire works of Shakespeare can be hidden in one digital photo. Kudos to Dr Pound for yet another extremely clear and understandable explanation of a complex topic!

A fairly good example of steganography that you may have come across without realising was the video game Spore. In it, you could drag the images of creatures/spaceships/buildings/etc. into the game's editor and it would then read the hidden data describing that creation from within the image and load it into the editor.

I could listen to this guy for ages and never get bored. The topics he presents are so fascinating and he presents them very well. Nice work

I cant understand a word of what he is saying. But I cant stop listening...

Okay, the message at the start had me laughing.

Subtitles are great "Stake in a graphic", and the best thing is that it never writes the same thing for jsteg : "chased egg" is my favourite.

Wikileaks had an strange email with a load of photos of Antarctica in. this guy needs to look at them....

I played around with this a bit in the late '80s. I wrote a program that would take a TGA file and put the message in the two least significant bits of each channel, just as he describes in the video. I found that I could tell the point at which the message stops, because the image just gets a bit less noisy and more clean. This could be an indication to someone else that you were hiding a message, if they were familiar with the process.

My solution was to generate random numbers and do the rest of the pixel data randomly. If your message is encrypted (which it should be; steganography is no substitute for sound encryption), then it should be indistinguishable from randomness anyway, so this should successfully hide the fact that you've hidden a message to begin with.

Of course, this isn't going to work with lossy algorithms like JPG. Today, just use PNG.

My professor didn't give us any detailed explanation on this topic but you gave a wonderful one. Thank you!

I am very glad you didn’t just show us the image and have us take your word for it that the images were different!

I must have watched a million Tech videos and read three times as many online articles before I found this guy here on computerphile and I have come to realize without question that this man is dangerous. Very few people possess this level of knowledge and the videos are by far the best on the internet. Keep up the good work!👍👍

I know that it should not be possible to see, but I keep imagine that there is a hidden message in his sweater.

Every time I research and implement something, Computerphile releases a video within a week on the same topic. GG Computerphile.

you telling me that there are secret messages in the rarest of pepes?

I just remember feeling like some sort of turbo hacker for following a tutorial when I was like 13 to hide a rar archive in an image file.